Print cartridges for printers are typically single use commodities. Each cartridge contains a supply of ink, for example in an ink jet type printer. Once the ink supply is exhausted, the cartridge is discarded or recycled, and a new cartridge is loaded into the printer. Many cartridges are not designed to be refilled, or to be replaced with non-printer specific cartridges. Print cartridges contain a memory among other components. The memory may contain parameters corresponding to various physical characteristics of the cartridge, including by way of example only and not by way of limitation ink type, ink color, ink quantity, date codes for manufacture of cartridge and ink, cartridge serial number or identifier, and the like.
Radio frequency identification (RFID) operates on well known principles. The requirements for a simple RFID system include an antenna or coil, a transceiver, and a transponder. The transceiver generates signals which are emitted by the antenna as radio signals. In some RFID systems, the transceiver and antenna are combined with a decoder and called an interrogator. The radio signals excite or activate an RFID tag containing the passive transponder. The tag transponder emits a signal in response to the received radio signals. This response is received and interpreted by the transceiver/decoder. RFID tags can contain a relatively large amount of data stored in on-tag non-volatile memory. Many passive RFID tags are programmed only once with data, and are not re-programmable. Some RFID tags carry a non-volatile memory that can be programmed, such as a flash memory, an electrically erasable programmable read-only memory (EEPROM), or the like. Active RFID tags have an internal power source, and are typically read/write capable.
In many areas, validation of print cartridges is important. For example, in a printer in which a certain type of cartridge or quality of cartridge is required, or in which an authentic cartridge specifically designed for the printer is required, the large number of cartridges available that all have the same basic configuration could result in an incorrect, improper, or non-authentic cartridge being used in a printer, potentially damaging not only the cartridge, but the printer and perhaps any media on which the printer is used. Simple validation techniques such as detecting a correct size or ink configuration of an ink cartridge are already performed on some printers using the information stored in the memory of the print cartridge. However, since such information is relatively standard and known, compromising the simple validation techniques currently used is not a complex process.
For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for a validation system more resistant to compromise.